POLYPODIUM VULGARE POTENTILLA CANADENSIS. 55 



Polypodium vulgare L. Fern family (Polypodiaceae). 



Common polypody; fernroot; rock-brake; female-fern. 



Native fern, 3 to 10 inches in height, with a perennial, creeping rhizome; on 



shady, rocky banks, in woods and mountains almost throughout North 



America. 



Parts used. — Rhizome and tops (nonoflBcial). 



Polypody, common. See Polypodium vulgare. 



Polytrichum juniperinum Hedw. Haircap-moss family (Polytrichaceae). 

 Haircap-moss; robin's-rye. 



Native moss, 4 to 7 inches in height, growing along margins of dry woods and 

 exposed places, mostly on poor, sandy soil. 



Part used. — Whole plant (nonofficial). 



Pond-lily, large yellow. See Nymphaea advena. 



Pond-lily, white. See Casta! la odorata. 



Poolroot. See Eupatorium ageratoides, E. aromuticum, and Sanicula marilandica. 



Pool wort. See Eupatorium ageratoides and E. aromaticum. 



Poplar, silver. See Populus alba. 



Poplar, silverleaf-. See Populus alba. 



Poplar, trembling. See Populus tremidoides. 



Poplar, tulip-. See Liriodendron tulipifera. 



Poplar, white. See Popidus alba and P. tremuloides. 



Poplar, yellow. See Liriodendron iidipifera. 



Populus alba L. Willow family ( Salicaceae). 



White poplar; silverleaf-poplar; silver poplar; white-bark. 



A large tree, sometimes 120 feet in height, naturalized in the United States; 

 occurs along roadsides from New Brunswick to Virginia. 



Part used. — Bark, collected in spring (nonofficial). 

 Popidus balsamifera candicans A. Gray. Same as Popidus candicans. 

 Populus candicans Ait. Willow family (Salicaceae). 



/Synonym. — Populus balsamifera candicans A. Graj^ 



Balm-of-Gilead. 



A large tree, about 80 feet in height, mostly escaped from cultivation, New 



Brunswick to New Jersey, west to Minnesota. 

 Parts used. — Leafbuds and bark (nonofficial) . 



Populus tremuloides Michx. Willow family (Salicaceae). 



Quaking aspen; American aspen; white poplar; trembling poplar; quiverleaf. 

 A slender, indigenous tree, growing in dry or moist soil from lower Canada south 



to Kentucky and in the Rocky ]Mountains to Lower California. 

 Part used. — Bark, collected in spring (nonofficial). 



Porteranthus trifoliatus (L.) Britton. Rose fam.ily (Rosaceae). 



Synonym. — Gillenia trifoliata Moench. 



Indian-physic; Bowman's-root; false ipecac; western dropwort. 



Native,~perennial herb, 2 to 3 feet higli, found in moist, shady places in rich 

 woods from New York to Michigan, south to Georgia and Missouri; more 

 common in the Atlantic States than in the Western States. 



Part used. — Root (nonofficial). 



Potato, hog-. See Ipomoea pandurata. 



Potato, wild. See Ipomoea jiandurata. 



Potentilla canadensis L. Rose family (Rosaceae). 



Fivefinger; cinquefoil. 



A 'small, annual or biennial i)lant, with creeping stems, growing in dry soil from 



Quebec to Georgia, west to Minnesota and the Indian Territory. 

 Part used. — Plant (nonofficial). 



